A099668 a(n) is the largest prime before A002282(n) repdigits.

7, 83, 887, 8887, 88883, 888887, 8888861, 88888883, 888888887, 8888888837, 88888888859, 888888888887, 8888888888857, 88888888888873, 888888888888883, 8888888888888753, 88888888888888801, 888888888888888859

Offset

1,1

Links

Table of n, a(n) for n=1..18.

Example

n=2: 83 is before 88.

Mathematica

<<NumberTheory`NumberTheoryFunctions` Table[Table[PreviousPrime[8*(10^n-1)/9], {n, 1, 35}]
Table[NextPrime[FromDigits[PadRight[{}, n, 8]], -1], {n, 20}] (* Harvey P. Dale, Jul 12 2014 *)

Crossrefs

Cf. A003618, A003617, A096497, A096498, A068104, A002275-A002283, A099656-A099667.

Sequence in context: A075137 A268704 A370522 * A348303 A240170 A231259

Adjacent sequences: A099665 A099666 A099667 * A099669 A099670 A099671

Keyword

base,nonn

Author

Labos Elemer, Nov 17 2004

Status

approved